Leveling a garage floor

by Kyle
(Iowa)

Q. My garage is sloped in two directions. About 5 to 6 feet inside the garage door the concrete is sloped to the door and the rest of the garage is sloped towards the house. I have had a couple suggestions and both of those required removing and re-pouring the entire garage.

The contractor was not familiar with pouring an overlay as thick as this may need and wasn’t sure how to successfully taper it at the garage door. I’m asking if this might be a possible choice for my situation. I would say the difference from the highest point to the lowest point (near the house) might be as much as an inch or two.

A trench drain would also work to catch snow melt but would need to run down the sides of both cars and across the front near the house to keep water away from the walls.

A. If you have the height to raise the concrete floor 1.5 inches, you can use a pea-stone concrete mix and pour a new floor over the existing one.

I would find the highest point of the existing concrete floor, go 1.5 inches over that, then raise the back of the floor enough to get pitch away from the house and to the garage doors.

Use a 4000 3/8 mix with fibermesh. Roll on a bonding agent like Weld-Crete to your clean and dry concrete floor before the new pour.

Install and finish the new concrete, taper the doors the same as a regular pour, saw expansion joints after it has hardened and spray on a concrete sealer.

Using a bag mix to overlay would be very expensive and difficult to get the proper pitch at that thickness.

If you cannot raise the floor that much then taking out the existing floor is the only other option.

Comments for Leveling a garage floor

I "can" go higher with the floor everywhere except the walk-out door but it is positioned on the side of the garage just around the corner from the overhead door (at the forward edge of the side wall). Would I need to raise this door?

What do I do at the walls? Do I simply remove the base boards and pour up to the sheetrock?

How do I taper at the overhead door? I don't mind a lip just inside the door if that'll work.

Would the pea gravel be visible once finished and can it be epoxy coated?

Has this been done successfully and lasted years?

Thanks!

A. If the side door opens to the inside of the garage and has a sill plate under it, open the door and measure the clearance from the bottom of the door and the concrete floor. It should be close to 1 1/4". If that is the case, you can pour the new floor up to the bottom of the door. Just make sure the door opens without dragging on the new concrete floor. That can be done while the new concrete is still "wet" by the concrete floor contractor.

If you don't have that amount of height under the door then it will have to be adjusted to accommodate the new floor.

You will need to install an isolation strip against the sheetrock so the concrete doesn't come into contact with it. A piece of 6 mil poly or some sill sealer will work fine. Tape this to the wall with some blue painter's tape, pour up against it, then trim whatever is above the floor after the floor hardens.

We taper the garage doors like normal, then build the driveway up with some cold patch if it is asphalt. If you have a concrete driveway then stopping the pour just behind the door is ok. You'll have a 1.5 inch "bump" to drive over. I prefer building the driveway up if possible.

The pea-stone concrete is power troweled smooth just like regular concrete. We have done this many times. You should have a nice smooth finish when the concrete floor contractor is done.

You can epoxy, acid stain, or polish the floor after it is done. You can also add color to the pea stone mix when it is poured if you want a decorative floor.